Method and apparatus for making a heel



'Au 11, 1936. V Y 2,050,348

METHOD AND APPARATUS FOR MAKING A HEEL Filed Jan. 24, 1935 5Sheets-Sheet 1 //v VE/V TUEL #man ea? Aug. 11, 1936. F. c. LOVEJOY' 7IiFlg 7 .Ja F

Aug. 11, 1936. F. c. LOVEJOY 8.

METHOD AND APPARATUS FOR MAKING A HEEL Filed Jan. 24, 1955 5Sheets-Sheet s Patented Aug. 11, 1936 PATENT OFFICE METHOD AND APPARATUSFOR MAKING A HEEL Fred C. Lovejoy, St.

Louis, Mo., assignor to United Shoe Machinery Corporation, Paterson, N.J., a corporation of New Jersey Application January 24, 1935, Serial No.3,324

Claims.

The present invention relates to the making of heels and, in particular,to the making of wood heels. It contemplates a novel method of makingheels, a machine comprising a novel combi- 5 nation for use in thepractice of the method, and

the novel heel resulting therefrom.

The lateral and rear surfaces of wood heels are shaped in a turningmachine, such as is shown in United States letters Patent No. 1,488,534,granted April 1, 1924, upon application of Folsom, Vinton and Whitney,in which the heel blank is held upside down upon a jack which rotatesupon a vertical axis located under the breast portion of the blank. Thejack is also tiltably mounted on an axis perpendicular to the firstdescribed axis, and extending from side to side of a heel blank in thejack. The tilting movement is effected by a cam track (known as theupper track) upon which rests that end of the jack arm which is handledby the operator to swing the jack. The vertical axis of rotation i isphysically represented by a shaft which carries the jack and which hasan arm at its lower end extending at right angles to the shaft. This armrests upon a second cam track (known as the lower track) which, like theupper track, is high at its middle and low at its ends, and which liftsthe jack shaft and jack as the jack turns to move one side of the heelover the cutter.

The heel is cut from the breast portion around to the center line of theback in one swing of the jack, and the other side of the heel issimilarly cut on a second cutter, the machine being a twin machine. Thevertical shaft-axis of the jack is swingable, in a gate member, from onecutter to the other, and when in position before either cutter has aslight in-and-out movement controlled by a heel-shaped form on the jackand a gage or rub collar which extends around in front of the cuttershaft. The form determines the depth to which the heel falls into thecutter and determines generally the shape of the horizontalcross-section of the heel, for example, the shape of the attaching face.

Thus, the sides and back of the heel will both fit the profile of thesurface of revolution generated by the cutter, but, owing to the liftingof the jack by the lower track as the jack turns, the back of the heelfits higher up on the profile than the breast portions do. In otherwords, the heel blank, aside from the progressivetilting movement causedby the upper track, moves over the surface of revolution generated bythe cutter head with a'screwing or helical motion, the axis of the screwor helix being parallel to that of the cutter head.

I have found that a novel and ornamental heel shape can be generated bypassing a heel blank over a suitable cutter by the movements'abovedescribed. The contemplated cutter head is of ordinary mechanicalformation, its peculiarity residing in the shape of its cutting edges.Instead of being. ground on a continuous curve, these edges are nicked,and consist, at leastin 10 part, of a series of teeth joined by concavearcs. The surface of revolution generated by this'part of the cutterhead is composed of circular flutes lying in planes perpendicular to theaxis of rotation of the cutter head, and the helical movement 15 of theheel blank over this surface results in a shape at any point which issubstantially complemental to the projection of the profile of thesurface on a plane passing through that point of the heel andperpendicular to the actual directionv of movement of that point at thetime, relatively to the cutter, that is, a plane passing through theideal instantaneous axis'on which the heel blank is actually turning atthe instant, and also through that locality on the heel which the cut-'ter is finishing at that instant.

1 The central part of both cam tracks is substantially horizontal, sothat when the back of the heel is being cut the pitch of the helicalmovement is negligible, the movement of the surface at the back of theheel being therefore substantially at right angles to the cutter axis.This results in impressing the effective profile of the cutter head onthis part of the heel, which therefore has a series of beads,corresponding to the flutes of the cutter head surface of revolution, atthis locality. The lifting movement of the jack is more pronounced asthe breast is approached (regarding the cut as being from the back tothe breast), and the profile of the cutter surface of revolution thenprojects into a series of shallow beads joining one another at obtuseangles, which causes the beads at the rear of the heel to shade intoshallow flutes at the sides.

Accordingly, the method of the present invention, in a broad aspect, maybe defined as moving a rotating cutter blade with'a cutting edge portionformed of teeth joined by concave arcs, and a heel blank surface, pasteach other in a direction oblique to the cutter axis.

As herein illustrated, the practice of the above method involves the useof a rotating cutter head having an effective surface of revolutioncomprising a series of arcuate flutes in planes perpendicular to theaxis of the cutter head, a jack shaft rotatable on an axis parallel tothe cutter head axis and arranged to carry the side and rear surfaces ofa heel blank past the cutter head, and a cam for moving the jack shaftin a direction substantially parallel to the cutter head axis as the outbetween the breast and the back of the heel blank is made, and inventionis to be recognized in the provision of such mechanism.

Regarded in another aspect, invention is further to be recognized asresiding in the novel heel produced by the above method, the characteristics of which have already been pointed out;

These and other aspects of the invention will be understood from theannexed specification and drawings, in which Fig. l is a side view ofthe machine by means of which the invention is practiced;

Fig. 2 is a plan view, which, like Fig. 1, shows the condition of thingsat the finish ofthe cut, at the back of the heel;

Fig. 3 is a detail showing the condition at the beginning of the cut atthe breast;

Fig. 4 is an enlarged view showing the end of the cut;

Fig. 5 is a diagram illustrating the intermediate portion of the cut;

Fig. 6 is an enlarged view showing the beginning of the cut; and

Figs. 7 and 8 are lateral and perspectiveviews of the heel produced.

A- machine by means of which the method is practiced will be firstdescribed. It comprises a vertical frame l0 having two vertical cuttershafts I2, I 4 at the top of each of which is mounted a cutter head l6.Eachcutter head has'two blades l8 the edges of which have generally theprofile of the side and rear surfaces of an inverted heel, but areground to exhibit a series of teeth 20' joined by concave arcs- 22. Allfour of the cutter edges are ground alike and the blades are set so thateach tooth on one blade swings exactly in the path of a. tooth on theother blade of that cutter head.

A vertical rotatable shaft .24 is mounted inbearings on the front faceof the frame I0 and carries a gate member 26 havlngbearings'lain itsouter end to support the vertical jack shaft 30. The shaft 30 is bothrotatable and slidable in the bearings 28, and its height is determinedby its arm 32 which rests on a cam or.lower track 34. This trackisroughly semicircular, and is higher in the middle than at the ends. The.upper end of the jack shaft 30 carries a head 35 in which the jack ispivoted at 38. The jack consists of a frame 40, pivoted to the head 36at 38, the frame having a fixed lower'jaw 42 and a movable upper jaw 44operable by a handle 46 to clamp a heel blank 48. The pivoted axisextends in a di-- rection running across the heel blank 48 from side toside, and is located below the heel blank. The jack with the blank in itis rotatedin front of a cutter head l6, from a position in which thevertical central plane of the heel blank lies across the front of themachine (Fig. 3), parallel to the plane of the two cutter shafts, to aposition at'right angles to this (Fig. 2), thus making a quarter turnabout its axis 30. During this turn' the handled end of the jack ridesaround on a cam or upper' track 50 which is preferably hingedly mountedon the front of the frame Ill; (This pivoted mounting of the track isexplained in United States Letters Patent No. 1,247,335, grantedNovember 20, 1917, on the application of H. W. Russ.)

The depth of cut into the heelblank 48 is determined by a form 52mounted on the jack shaft 30 under the head 36, which runs against anadjustable rub collar 54 which extends around in front of the cuttershaft. The gate member 26 swings a little during the heel cutting topermit the form and rub collar to remain in contact.

The operation above described cuts the lateral heel surface from thebreast to the center of the back, on one side, and the other side is outagainst the other cutter in the same way. The two cutter heads run inopposite directions such that each cutting edge travels rearwardly onthe heel blank, and the two cutter heads are necessary in order to avoidcutting against the grain of the wood, which runs from front to back.

Thus, in cutting from one side of the breast to the back, the heel blankis tilted into the cut ter by the upper track and is raised along theefiective shape of the cutter so that the back of the finished heelcorresponds to a locality farther up on the cutter profile than thebreast portions do. The central portion of the lower track is horizontalso that as the locality adjacent to the center of the back of the heelis cut the movement past the cutter of the heel surface then being cutis perpendicular to the axis of the cutter. This will cause the exactprofile of the effective shape of the cutter to be shaped on the heel inthis neighborhood, which is cut into a series of beads 55 (Fig. 4). Atthe sides of the heel, however, the heel rises vertically during thecut, so that the movement of a lateral point of the heel over the cutteris oblique to the axis of the cutter (see Fig. 6).

The effective shape of the cutter head is thus changed and becomes theprojection of the periphery of the actual whirling shape it generatesupon a plane correspondingly oblique to its axis. that is, on a planeperpendicular to the line of relative travel of the heel surface and apoint on a cutting edge at that instant. In this way the lateral heelsurface is shaped into a series of shallow flutes 58 or concave grooveswhich gradually merge into the beads 56 formed at the back.

This is illustrated in Figs. 4, 5 and 6, the former .of which shows ashape like that of the cutter head when viewed in a directionperpendicular to its axis, and the latter of which shows the appearanceof the same shape when viewed in a directionoblique to its axis.

The intermediate Fig. 5 illustrates the phenomenon of transition fromthe condition shown in Fig. 6 to that shown in Fig. 4. The whirlingshape of the cutter head is illustrated in all three of these figures.The profile of this whirling shape is composed of. elliptic arcs taken(see Fig. 5) from the ellipses a, which represent the circular paths ofthe teeth and the approximate ellipses b which are the projections ofthe approximately circular arcs between the teeth of the cutter. It willbe seen that as the angle between the direction of movement of the workand the cutter axis becomes more and more oblique, that is, as the Fig.4 position changes toward the Fig. 6 position (regarding the cut as madebackwards) the ellipses a gradually overlap the ellipses b, until theeifect of the latter completely disappears.

It will be noticed (Fig. 7) that the flutes 58 diverge as they approachthe breast of the heel blank. This is due to the tilting action of theupper track. Again regarding the cut as made in the reverse direction,from the back to the breast, the jack tilts backward, away from thecutter, and the top-lift end of. the heel blank is carried nearlyhorizontally away from the cutter, while the attaching face end of theheel blank is lifted vertically, partially counteracting the drop due tothe slope of the lower track. This causes a progressive change in theslope of the flutes, from top-lift end to the attaching face end of theblank.

If the lower track were horizontal, the heel blank would be beaded allthe way around, and if. the upper track were horizontal, the fluteswould all be parallel.

It may be remarked that, owing to the facts that the direction ofrelative movement between the heel blank and the whirling shape of thecutter is continually changing and that the teeth of the cutter are notabsolutelysharp-pointed, Fig. 5 is a suggestive, rather than arigorously accurate, showing of the conditions intermediate between Fig.4 and Fig. 6.

While the cutters have been shown as toothed throughout their cuttingedges, the claims are not to be understood as limited to suchconstruction. The invention also contemplates ornamentation .of heelsover a part of their side and rear surfaces, merely.

Having described my invention, what I claim as new and desire to secureby Letters Patent of the United States is:

1. That improvement in the art of making wood heels which comprisesrotating a heel blank past a rotating cutter the cutting edge of whichconsists of substantially equally spaced teeth joined by concave arcs,the direction of. movement of that part of the surface of the heel blankthat is in contact with the cutter being generally oblique to the axisof the cutter.

2. That improvement in the art of making wood heels which comprisesrotating the side and rear surface of a heel blank past a rotatingcutter the cutting edge of which comprises a plurality of teeth joinedby successive concave arcs, the axis of rotation of the heel blank beingparallel to that of the cutter, and shifting the heel blank parallel tothe axis of the cutter during the out between the breast and the back ofthe heel blank, whereby the movement of that part of the surface beingoperated on at any instant is enerally oblique to the axis of thecutter.

3. That improvement in the art of making wood heels which compriseseffecting a relative helical movement between the lateral and rearsurfaces of a heel blank and a rotating cutter head, the effectivesurface of revolution generated by which comprises a plurality ofcircular flutes, the axis of the said helical movement being parallel tothe axis of the cutter head.

4. That improvement in the art of making wood heels which comprisesmoving past each other with a helical motion the side and rear surfacesof a heel blank and a rotating cutter head having an effective surface.of rotation composed of circular flutes lying in planes perpendicularto the axis of the cutter head, the axis of the cutter head and the axisof the helical motion extending generally in the same direction.

5. In a machine for turning heels, a rotating cutter head having aneffective surface of revolution comprising a series of arcuate flutes inplanes perpendicular to the axis of the cutter head, a jack shaftrotatable on an axis parallel to the cutter head axis and arranged tocarry the side and rear surfaces of a heel blank past the cutter head,and a cam for moving the jack shaft in a direction substantiallyparallel to the cutter head axis as the out between the breast and theback of the heel blank is made.

FRED C. LOVEJOY;

